This invention relates generally to imaging devices, and more particularly, to automatically positioning a structure within the field of view of the imaging device
The medical imaging industry has developed many different types of imaging systems that are useful for diagnostic purposes. Some systems image using a single modality, such as computerized tomography (CT), positron emission tomography (PET), and nuclear medicine (NM). Other systems offer a combination of imaging systems, such as CT-PET and CT-NM, and may be referred to as multi-modality systems. The multi-modality systems may acquire images using one modality or acquire images in more than one mode simultaneously.
When imaging a specific structure, organ or anatomy of a patient, such as the heart, liver or kidney, the patient must be positioned in relation to the detector or camera of the imaging system such that the structure to be imaged is within the field of view (FOV) of one or more imaging detectors. Certain scanning methods, such as nuclear tomography cardiology scanning, wherein the detector(s) rotate around the patient, require patient positioning so that the heart is as close as possible to the center of the detector's FOV. If the patient is not positioned correctly, the scan must be stopped and the patient repositioned. In other cases, the positioning problem may not be apparent during the acquisition, and thus acquired data may be reviewed and/or processed before it is found to be deficient.
Within NM, the patient is typically positioned by an operator who manually adjusts the patient table and the imaging detector(s) while viewing the persistence image until the operator determines that the patient's heart or other structure of interest is centered within the FOV of the detector(s). This may be cumbersome and time consuming depending upon the location of the monitor displaying the persistence image, as well as adding to the discomfort of the patient who needs to lie still on the patient table during the positioning. Manually positioning the patient becomes increasingly complex with PET systems, as well as with an NM camera having a multi-pinhole collimator or when the NM camera FOV is small, such as in dedicated cardiology systems.
Therefore, a need exists for automatically positioning a patient within the FOV of the imaging detector(s) of a medical imaging system. Certain embodiments of the present invention are intended to meet these needs and other objectives that will become apparent from the description and drawings set forth below.